| Traitements de prescrit brûlures |
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One of the overall objectives of the EMEND project is to determine which forest harvest
and regenerative practices best maintain biotic communities, spatial patterns of forest structure,
and functional ecosystem integrity in comparison with mixed-wood landscapes that have originated through
wildfire and other inherent natural disturbances. As such, one of the "controls" at the EMEND site is
prescribed fires. The following is a description of the burn prescriptions and the burns to date.
Pre-assessment:
Transect survey for Dead and Downed Woody Debris and placement of Depth of Burn pins is done prior to the burns.
Prescription criteria:
For each stand type, upper and lower limits are set for the Fire Weather Index (FWI) , Drought Code (DC), Fine Fuel Moisture Code (FFMC),
and Duff Moisture Code (DMC). These codes are all part of the Canadian Forest Fire Danger Rating System.
Prescriptions:
1) Deciduous dominant: Burned prior to May 21 (estimated leaf flushing date). No limits on the DC, or FWI. FFMC > 84 and DMC 25-40.
2) Deciduous with understory: Burned anytime. DC < 300, FWI 4-18, FFMC > 84, DMC 25-40.
3) Coniferous dominant: (coniferous dominant and mixed conifer/deciduous)
Burned anytime with a DC < 250, FWI 4 -18, FFMC > 84, and DMC 25-40.
Prerequisite Weather and Fire Indices:
The actual indices and codes that exist on the day of burning are used to predict fire behavior and effects.
These codes are used as indices to assess when to burn but the final decision is made by the "on-site" ALFS
ignition team.
Ignition:
Ignition and control of burns is conducted by Alberta Land and Forest Service (ALFS).
All burns to date have been ignited by ALFS using an aerial drip torch.
Fire Control:
Fire guards that are bladed to mineral soil have been cleared around the sites to be burned and
adequate ground and air resources are present and available "on-site" during and following ignition.
ALFS ground suppression crew for compartment 926 burn
Post Assessment, Classification:
Following the burn, another transect survey of Dead and Downed Woody Debris and measurement of Depth of Burn pins are used to estimate the Total Fuel Consumption. Total Fuel Consumption and
Rate of Spread can provide an estimate of the Fire Intensity.
Burns to date: (need to add some notes and pictures for these burns)
1) Conifer dominant compartment 926 (burned late July 1999).
Compartment 926 was the first experimental burn attempted at the EMEND site. The fire burned hot and with a medium rate of spread.
The burn was patchy with some areas burnt to mineral soil and other areas with no evidence of burn.
Compartment 926 post fire (photo taken summer 2001)
2) Deciduous dominant compartment 943 (burned April 2000).
3) Deciduous dominant compartment 856 (burn attempted May 2001).
Compartment 856 burn was considered not successful. The fire did not spread from points of ignition and no trees were killed by fire.
The only fuels consumed were grass and the occassional snag.
Burning snag, compartment 856.
